Volatile

1. (physics) Evaporating or vaporizing readily under normal conditions.
2. (of a substance, informal) Explosive.
3. (of a price etc) Variable or erratic.
4. (of a person) Quick to become angry or violent.

5. Fickle.
6. Temporary or ephemeral.
7. (of a situation) Potentially violent.
8. (computing, of a variable) Having its associated memory immediately updated with any changes in value.
9. (computing, of memory) Whose content is lost when the computer is powered down
10. (obsolete) Passing through the air on wings, or by the buoyant force of the atmosphere; flying; having the power to fly.